This invention relates to containers and packaging, and is particularly concerned with the provision of containers and packaging which can be re-used. In one aspect the invention relates to containers having a closable opening, including those used commercially for the storage and transportation of a wide variety of products. A particular aspect of this invention is concerned with such a closable plastics container which, because of the nature of the sealing device, is reusable on many occasions.
Flexible containers are widely used in industry for the transport and storage of solid products. In particular, the use of plastics bags or containers for the storage and transportation of materials has found widespread application in industry because of the strength, flexibility, lightness and inert nature of such containers, and the fact that they are relatively inexpensive to produce.
Specifically, plastics bags find application as flexible intermediate bulk containers (FIBCs) and as liners for rigid intermediate bulk containers (RIBCs). FIBCs and RIBCs normally have a capacity of up to 3000 liters and more typically have a capacity of about 1000 liters. Depending upon the density of the contents, therefore, a 1000 liter FIBC may carry a load of up to about 1500 kg. Such containers are used for the storage and transportation of materials in powder, granule or paste form, for example chemical raw materials and foodstuffs. FIBCs may have an inner liner and do not require further packaging. FIBCs are typically designed to be lifted from above using integral, detachable or permanently attached lifting devices.
FIBCs are generally comprised of plastics such as polyalkenes, typically polyethylene or polypropylene, or polyesters, for example; alternatively they may be made of woven fabric or of paper. One class of container is made using sheet plastics laminate material. The containers are typically reinforced, for example by a fabric or alternatively by fibres, and may comprise laminates of such reinforced or non-reinforced polymers with aluminium; optionally, further materials may also be incorporated. One exemplary material is a cross-laminated HDPE film sold under the registered trade mark Valxc3xa9ron by Van Leer Flexible Packaging, PO Box 88, B 2910 Essen, Belgium.
Plastics bags also find application for somewhat smaller bulk containers, for example with a capacity of about 25 liters. One 25 liter flexible plastics container has a paper lining and is used for the transport and storage of dry foodstuffs, especially rice.
Another type of flexible container is a pallet cover, which is typically heat-sealed plastics sheeting enclosing a pallet and one or more articles loaded on the pallet. As the skilled reader will appreciate, there are numerous other containers which are formed from flexible packaging material, especially sheet plastics material.
Prior to the transportation of goods in containers, it will be appreciated that sealing of the containers is required in order to protect the goods and/or prevent loss through spillage or leakage of materials in transit. Most commonly, sealing is achieved by the application of an heat and, to this end, the incorporation of a reliable heatseal medium in the material of the containers ensures that an effective seal may be obtained. Whilst such means ensure that high efficiency of sealing is achieved, once the seal is broken, for example following transportation, and the contents of the container have been removed, re-use is not possible, and the used container has to be disposed of in a suitable manner.
It has therefore been desired to provide flexible containers, especially plastics bags, which are for the transport of bulk goods and which are both sealable and re-usable. A perceived problem in achieving this aim has been the incomparability of known fasteners with such plastics bags (and other flexible containers) in view of the heavy loads carried by bulk containers. For example, very small bags are known to be sealed using mating profiles or zips, but both these types of fastener have been perceived as offering inadequate strength when placed in a bulk container.
Those very small plastics bags which do incorporate zips use stitching to attach the zip to the plastics sheeting of the bag. Whilst the stitching provides strength and has proved itself as a reliable attachment means, it is relatively costly and inconvenient to provide, such that an even more ideal re-usable fastener would be attached by means which would be relatively inexpensive and convenient to attach but nonetheless provide strength and durability.
It would therefore be desirable to provide a resealable flexible bulk container especially a resealable flexible plastics bulk container. It is an objective of a preferred embodiment of the present invention to provide a plastics container in the form of a plastics bag which may be used as an FIBC or as a liner in an RIBC, and which may be reused on several occasions.
It would also be desirable to provide a plastics bag provided with a robust re-usable closure capable of being attached to the body of the bag by a means more convenient than stitching.
According to one embodiment of the present invention, there is provided a flexible bulk container, especially a flexible plastics bulk container, having an opening which is closable by means of a zip fastener. The container in some preferred embodiments is an FIBC or a liner for an RIBC. In other preferred embodiments, the container is a pallet cover or an order picking container.
According to another embodiment of the present invention, there is provided a plastics bag, which may be a bulk container, having an opening which is closable by means of a zip fastener attached to the body of the bag by means of an adhesive or by welding. The bag is typically comprised in a bulk container having a capacity of about 25 liters or more, e.g. 500 liters or more. In one class of embodiments the bag is an FIBC or a liner for an RIBC having in either case a capacity of about 1000 liters, or it may be bigger. In another class of embodiments the bag is a pallet cover.
By the use of an adhesive or welding in this way it is possible conveniently to adhere the plastics backing of the zip mechanism to the surface of the plastics bag at either side of the opening therein. Thus, the plastics bags of this aspect of the invention are very easy to produce and operate and, once emptied of their initial contents and cleaned internally, the bags are available for re-use, leading to further cost savings in addition to the environmental benefits which accrue as a result of the reduction in waste.
In all embodiments of the invention the zip preferably comprises plastics material the same as or similar to that of the bag, in order that compatibility with the proposed contents may be ensured. Thus, the surfaces of the zip preferably comprise a plastics material having compatability properties similar to those of the bag. In those embodiments of the invention which do not require the zip to be glued to the container or bag, as in the case of intermediate bulk containers, it may be stitched to the body of the container or bag.
The zip may extend across the top of the flexible container or bag, or it may be located in a sidewall thereof, as is preferred in the case of pallet covers, FIBCs and RIBC liners. Thus, the invention includes pallet covers, FIBCs and RIBC liners which are made using plastics sheet material (which may be reinforced and/or laminated) and comprise in a sidewall thereof an opening provided with a zip fastener, which is suitably in an upright orientation in use and may have a length of, for example, 25-50 cm, e.g. about 30 cm.
The body of the flexible container may comprise any plastics material known for the construction of such containers. Thus, the plastics material may be reinforced and/or be laminated; such laminates may include non-plastics materials (notably metal foil, especially aluminium foil) as well as plastics materials. In some classes of container, an outer layer comprising flexible plastics film material, e.g. a reinforced polyalkane or polyester, is lined by an inner layer of, for example, paper. Of course, such reinforced polyalkane or polyester materials do not have to be lined. The invention includes containers suitable for providing thermal insulation and comprising bubble film optionally laminated to a metal foil material.
The adhesive utilised in some embodiments of the present invention may be applied as an adhesive strip, allowing the plastics of the zip fastener to be directly attached to the surface of the plastics bag. Most conveniently, the adhesive strip is in the form of a double-sided adhesive strip, which may conveniently be applied such that the zip fastener becomes affixed to the outer surface of the plastics bag. Alternatively, however, the zip may be attached to the inner surface of said bag. By this use of an adhesive it is possible to avoid the necessity to provide paper linings which were a feature of some prior art flexible containers and facilitated the attachment of plastics surfaces to each other with the assistance of various glues and other adhesives.
As has already been stated, the containers and bags of the invention may be in the form of pallet covers. The invention provides in a further aspect a reusable flexible pallet cover characterised in that it has, in use, an open bottom and in that, usually, it comprises a releasable fastener member for directly or indirectly holding the pallet cover to a pallet. Preferred embodiments are set forth in the claims.
The invention also includes a package comprising a pallet having one or more articles loaded thereon and, covering the articles, a flexible pallet cover open at the bottom and seated on or at least partially surrounding the pallet, the pallet cover being directly or indirectly held to the pallet by a releasable fastener member. Again, preferred embodiments are set forth in the claims.
Preferred pallet covers of the invention, as well as other containers, may be made from flexible packaging comprising cruciform sheet material. Such packaging forms a further aspect of the invention and has arms whose adjacent side margins are provided with respective members of a zip fastener for zipping the margins together. The zip fastener members are suitably adhered or welded to the sheet material.
The sheet material may comprise bubble film optionally laminated to a metal foil material. The invention also includes zippable bubble film packaging, for example containers, in other configurations.
Preferred embodiments of the cruciform packaging and the zippable bubble film packaging are set forth in the claims.